UL Wires and Cables Lists and Comparison Chart

UL Wires and Cables Lists

Wire&Cable Jacket Materials

• PVC
• PVC+Nylon
• SRPVC
• XLPVC
• PTFE
• ETPE
• FEP
• PFA
• XLPE
• Silicone

PVC (Polyvinyl Chloride)

PVC is the most widely used cable jacket material due to its excellent balance of properties, cost-effectiveness, and ease of processing. It offers good flexibility, decent abrasion resistance, inherent flame retardancy (often enhanced with additives), and resistance to water, acids, alkalis, and oils. Available in a wide range of colors and hardness levels (measured in Shore A), PVC jackets are versatile and suitable for general-purpose wiring in buildings, appliances, and control systems across various industries. While its temperature range (-40°C to 105°C) suffices for many applications, it can become brittle at very low temperatures and soften excessively at high temperatures compared to some alternatives. Environmental concerns regarding plasticizers and chlorine content are also considerations.

PVC + Nylon

Combining a PVC jacket with an extruded thin outer layer of nylon significantly enhances the cable's surface properties. The nylon overlay offers superior abrasion resistance, a reduced coefficient of friction (making the cable easier to pull through conduits), increased cut-through resistance, enhanced resistance to chemicals such as oils and fuels, and improved protection against environmental stress cracking. This composite jacket retains the electrical insulation, flexibility, and flame retardancy benefits of PVC while offering a much tougher outer skin. It's commonly used in demanding applications, such as industrial automation, robotics, appliance wiring, and control cables exposed to physical wear or harsh chemicals.

SRPVC (Semi-Rigid PVC)

SRPVC is a formulation of PVC designed for higher temperature performance and improved physical properties compared to standard flexible PVC. It achieves a stiffer, more rigid feel (hence "semi-rigid") while maintaining good impact strength. Its key advantage is an extended operating temperature range, typically rated from 105°C to 125°C, making it suitable for applications such as internal appliance wiring, lighting fixtures, and connections near heat sources where standard PVC might soften excessively. SRPVC also offers enhanced chemical resistance and improved dimensional stability under heat, although its reduced flexibility can be a limitation in dynamic applications that require constant bending.

XLPVC (Cross-Linked PVC)

XLPVC undergoes a chemical or radiation-induced cross-linking process after extrusion, creating covalent bonds between polymer chains. This transformation significantly improves the material's thermal and mechanical properties compared to standard PVC. XLPVC jackets exhibit much higher heat resistance (operating temperatures up to 125°C or more), superior cut-through resistance, enhanced abrasion resistance, improved resistance to deformation under load (compression set), and better resistance to solvents and chemicals. While more expensive and less flexible than standard PVC, XLPVC is ideal for demanding applications, such as industrial machinery, welding cables, and portable power cords, that require durability under thermal and mechanical stress.

PTFE (Polytetrafluoroethylene)

PTFE is a high-performance fluoropolymer renowned for its exceptional properties. It boasts an extremely wide operating temperature range (-200°C to +260°C), outstanding chemical inertness (resistant to virtually all chemicals), very low coefficient of friction, excellent dielectric properties, inherent non-stick characteristics, and high flame resistance (it self-extinguishes). These properties make PTFE ideal for extreme environments found in aerospace, military, chemical processing, high-temperature equipment, and high-frequency/signal integrity applications. However, PTFE is relatively expensive, requires specialized processing (sintering), and can be prone to "cold flow" (deformation under sustained pressure).

ETPE (Ethylene-based Thermoplastic Elastomer)

ETPE refers to a class of thermoplastic elastomers (TPEs) based on ethylene copolymers, often including materials like EPDM/PP blends or specific grades of POE (Polyolefin Elastomers). These materials combine the flexibility, elasticity, and softness typical of thermoset rubbers with the easier processing (extrusion, injection molding) and recyclability of thermoplastics. ETPE jackets generally offer good flexibility over a wide temperature range, excellent weather resistance (including UV and ozone), good chemical resistance, low-temperature flexibility, and halogen-free flame retardant options. They are increasingly used as alternatives to PVC or thermoset rubbers in applications such as solar cables, portable electronics, and outdoor wiring that require flexibility and environmental resistance.

FEP (Fluorinated Ethylene Propylene)

FEP is a melt-processable fluoropolymer closely related to PTFE but with slightly lower maximum continuous service temperature (typically -200°C to +200°C). Its key advantage over PTFE is its ability to be processed using conventional thermoplastic extrusion techniques. FEP retains excellent chemical resistance, near-zero moisture absorption, outstanding dielectric properties, low friction, and non-stick characteristics. It also has superior flame resistance and low smoke generation. FEP is widely used for high-performance wire insulation and thin-wall jacketing in demanding sectors such as aerospace, semiconductor manufacturing, medical devices, and plenum-rated cables, where its combination of properties and processability is crucial.

PFA (Perfluoroalkoxy)

PFA is another melt-processable fluoropolymer offering properties similar to those of FEP and PTFE. Its continuous service temperature range (-200°C to +260°C) matches PTFE, making it the highest-temperature melt-processable fluoropolymer. PFA provides exceptional chemical resistance, excellent dielectric properties, low friction, non-stick surface, high purity, and outstanding flex life (resistance to repeated bending). While more expensive than FEP, PFA is chosen for the most demanding applications that require the ultimate combination of high-temperature performance, chemical inertness, flexibility, and processability, such as critical aerospace wiring, high-temperature sensors, and semiconductor fabrication equipment.

XLPE (Cross-Linked Polyethylene)

XLPE is polyethylene that has been cross-linked, typically using peroxide (HVDC) or silane (MV/LV) methods. This process transforms the thermoplastic polyethylene into a thermoset material with significantly enhanced properties. XLPE offers superior thermal capabilities (operating temperatures up to 90°C or 125°C, depending on grade), much higher short-circuit ratings, improved resistance to environmental stress cracking, better moisture resistance, and excellent dielectric strength compared to standard PE. Primarily used as insulation for power cables (low, medium, and high voltage), XLPE is less common as a primary jacket material but can be used in specialized applications or as an outer protective layer over its insulation, valued for its toughness and environmental resistance.

Silicone (Polysiloxane Rubber)

Silicone rubber is an elastomeric material renowned for its exceptional flexibility over an extensive temperature range (-60°C to +180°C or higher for specialized grades). It maintains its elasticity and properties in both deep cold and high heat. Silicone offers excellent resistance to ozone, UV radiation, moisture, and a wide range of chemicals. It exhibits good electrical insulation properties and high flame resistance, typically producing low smoke and non-corrosive fumes upon combustion. Its softness and flexibility make it ideal for high-flex applications, coil leads, heating elements, and extreme environments. However, silicone has relatively low mechanical strength (in terms of abrasion and cut resistance) and can be swollen by certain solvents.

How to Choose the Correct Wire for Your Appliance?

1. See the Voltage​​

The voltage rating of wire insulation is paramount for safety. Choose wire rated at least for your appliance's nominal supply voltage, but significantly higher (e.g., 300V or 600V for standard 120/240V AC appliances). This accounts for voltage spikes and ensures insulation integrity under fault conditions. Using under-rated insulation risks a breakdown, which can lead to short circuits, sparks, or electrocution. Consider both the appliance's internal voltage needs and the supply voltage. Always prioritize insulation rated well above the working voltage to create a critical safety buffer. Matching the voltage requirement prevents insulation failure and protects users and equipment.

​​2. See the Temperature Requirement​​

Wires face heat from electrical resistance (I²R losses) and their environment (e.g., near motors, heaters, or inside enclosures). The wire's insulation and conductor must handle this combined temperature. Wire insulation is rated for maximum operating temperature (e.g., 90°C, 105°C, 125°C). Higher-rated insulation is essential for high-wattage appliances or locations with high temperatures. Conductor type (copper) also matters, as heat degrades insulation more quickly and can cause oxidation of connections over time. Always choose wire rated for the highest expected temperature in its installation spot. Ignoring this can cause premature insulation brittleness, cracking, and an increased fire risk.

​​3. See the Current Requirement​​

The wire's conductor size must safely carry the appliance's full load current without overheating. Use the appliance's wattage/amperage rating to determine the minimum required conductor size (expressed in AWG or mm²). Undersized wires overheat, damaging insulation and potentially causing fires. Follow electrical codes (such as NEC tables), which specify ampacities based on conductor material, insulation temperature rating, and installation method. Factor in continuous loads, which require derating (using wire sized for 125% of the load current). Verify if the appliance has inrush currents requiring a temporary higher capacity. Correct sizing prevents dangerous overheating.

For determining the correct wire gauge to match a specific current, refer to this article.

​​4. See the Connector Matched Conductor Size and OD​​

Physically matching the wire to terminals or connectors is crucial for reliable connections. Ensure the wire's conductor cross-sectional area matches the terminal lugs (e.g., ring or spade terminals accept specific AWG sizes). Equally important is the ​​Overall Diameter (OD)​​ including insulation. Wire that's too thick won't fit through strain reliefs, conduit, or connectors, while excessive flexibility can cause poor connections. Connectors specify compatible conductor sizes and maximum outer diameter (OD). Check appliance schematics and physical terminals for size limitations. A proper fit ensures secure terminations, minimizes strain, prevents shorts, and guarantees electrical reliability at connection points.